I tried to hook up a new B-A PV700 powered subwoofer to an old (1990) Pioneer VSX-D1S receiver using the receiver's "powered woofer output jack". The subwoofer performed as expected on music CDs, but when playing movies from a DVD player all I got was "muffled" noise from the subwoofer. I tried removing the RCA cable and hooked up the SWF using the receiver's front line level speaker jacks and now it works ok. Anyone have a guess as to why it wouldn't work with the dedicated subwoofer (RCA) cable? This receiver is too old to have a "speaker setup routine" as far as I know. I'm hoping someone familiar with this receiver can help. I'm thinking of upgrading the receiver anyway, but want to make sure the subwoofer isn't defective